A 3D-space object measurement technique is widely used for detecting and analyzing the shape, appearance and distance of an under-test object. Generally, by the 3D-space object measurement technique, a light beam is projected to the under-test object, and the distance of the object in the 3D space is calculated according to the reflection of the light beam. Since the measured data contains the depth information, the measured data is also referred as a depth image.
Generally, the methods for capturing the depth image of the object are classified into contact type methods and non-contact type methods. For example, a 3D gesture sensing control method is one of the non-contact type methods. Moreover, the 3D gesture sensing control method may be implemented by three major techniques, including a structured light scanning technology, a time-of-fight (ToF) measurement technology and a triangulation technology.
The structured light is a light with a specified pattern. When the light with the specified pattern is projected on the under-test object, the light is subjected to deformation. Consequently, a camera may be used to acquire the image information of the deformed structured light that is influenced by the object surface. The image information contains the distance of the object, the shape change of the object change or the object gap.
Therefore, it is important to generate an easily-read structured light for the 3D gesture sensing control.